Am.  Jour.  Pharm. 
Dec,  1892. 
Detection  of  Higher  Alcohols. 
627 
ammonia,  a  rose  colored  precipitate  with  gelatin  solution,  and  a 
chestnut-brown  precipitate  with  cinchonine  acetate.  The  acid 
therefore  belongs  to  the  classes  of  tannins  and  polyphenolic  substances. 
fi-Ampelochroic  acid,  which  is  stated  to  have  the  composition 
C26H24015,  bears  a  general  resemblance  to  the  a-acid.  It  forms 
cochineal-colored  crystals,  and  its  aqueous  solution  is  feebly  acid  to 
litmus  and  feebly  astringent  to  the  taste.  It  is  precipitated  by 
gelatin  and  by  cinchonine  acetate  ;  it  gives  a  violet  precipitate  with 
tartar  emetic,  a  dark-green  precipitate  with  zinc  acetate,  a  dirty, 
rose-colored  precipitate  with  mercuric  nitrate,  a  yellowish-brown 
precipitate  with  copper  acetate,  and  a  chestnut-brown  precipitate 
with  hot  silver  nitrate.  Potash  turns  the  color  of  its  solution  to 
yellowish-green,  and  ferric  chloride  gives  a  dark  violet  coloration, 
changing  to  a  brown  precipitate. 
A  third  acid  of  the  same  general  character  as  the  others  was 
obtained  from  the  first  fraction  or  blue  precipitate  formed  in  their 
preparation.  The  precipitate  was  suspended  in  water,  decomposed 
with  hydrogen  sulphide,  partially  saturated  with  baryta  water,  and 
the  whole  evaporated  to  dryness  in  a  vacuum.  The  residue  was 
extracted  with  ether  to  remove  impurities,  and  the  new  acid  was 
dissolved  out  with  alcohol. 
y-Ampelochroic  acid,  C17H18O10,  crystallizes  in  reddish-brown  octa- 
hedra  and  dissolves  readily  in  water  to  a  red  solution,  astringent  to 
the  taste.  With  gelatin  and  tartar  emetic,  it  forms  rose-colored 
precipitates  which  dissolve  on  heating ;  with  mercuric  nitrate,  it 
gives  a  pale,  greenish-blue  precipitate,  a  green  precipitate  with  cal- 
cium acetate,  an  olive-green  precipitate  with  basic  lead  acetate,  a 
dark  violet  to  brown  precipitate  with  ferric  salts,  and  an  orange  to 
yellow  precipitate  with  bromine  water.  Potash  changes  the  color 
of  its  solutions  to  olive-green. 
DETECTION   OF   HIGHER  ALCOHOLS  IN  SPIRITS  OF 
WINE.1 
By  C.  Bardy. 
A  preliminary  examination  is  made  by  agitating  10  cc.  of  the 
alcohol  with  cc.  of  a  saturated  salt  solution.  If  an  oily  upper  layer 
does  not  separate,  100  cc.  of  the  alcohol  is  agitated  with  450  cc.  of 
a  saturated  salt  solution  in  a  vessel  provided  with  a  stop-cock  ;  suffi- 
1  Compt.  rend.,  114,  1201-1204  ;  Jour.  Chem.  Soc,  Novb.,  1892,  p.  1379. 
